Flow restrictor



y 8, 1952 G. w. ALLEN HAL 2,602,468

FLOW RESTRICTOR 2 SlEETS-Si-IEET 1 Filed May 4, 1946 I I I .3 WW do .3115 M 9 G. w. ALLEN ETAL 2,602,468

FLOW RESTRICTOR Filed May 4, 1946 2 SHEETS-SHEET 2 Patented July 8, 1952rUNlTED STATES PATIENT 2,602,463 v FLOW RESTRICTOR.

George W.-Allen and Vernon N. Tramontini, In-

dianapolis, Ind assignors to Stewart-Warner Corporation, Chicago, 111.,a corporation of Virginia Application May 4, 1946 Serial No. 667,39530mm. (01. 138-42) is to provide-a novel control valve having apluralityof valve elements therein, operable iii-re sponse to temperatureconditions in the heating tion comprises a main casting l forming avalve body which mounts or houses-an automatic pressure regulator 12, anon-off solenoid operated valve l4, a second on-off solenoid valve l6,and a flow-restricting means l8. The valve body Iii should be aluminumor some other nonmagnetic metal and is formed with an inlet 20 and anoutlet 22, both of which may be provided with standard pipe threads forconnection 'into the fuel supply system of an internal combustionheater. The on-off valves l4 and I6 and I the flow-restricting, pressurereducing means I8 system including an internal combustion type heater toobtain high heat, 1ow heat, and no heat output.

Another object is to provide a novel unitary control valve which willsupply fuel to an internal-combustion heater at a rate designed to givethe desired optimum heat'output from the heater, in responsetoconditions existing in the heater and heating system.

' Another object is to'providea novel control valve in a single-unitwhich will supply liquid fuel to a heater of the internal combustiontype at a predetermined pressure regardless of the pressure at the inletto the control valve.

Another object is to provide a new and improved control valve whichincorporates one or more electromagnetical'ly operated valve members. 7r r A further object is to provide'a novel control valve incorporating aunique means'for reducing pressure and restricting fuelflowWithOUt'StOP-r ping the flow completely.

Still another object is toprovide a new and improved'control valvehaving the aforementioned advantages and which is comparatively simplein construction, rugged,and easily adjusted;

7 Other objects and advantages will become apparent from thefollowingdescription taken in conjunction with'the accompanying drawingsin which:'-

Fig. lis-a top plan viewof the novel control valve forming the subjectmatter of the present invention;

Fig. 2 is an end elevational view of the control valve;

Fig. '3 is asectional View on an enlarged scale taken substantiallyalong the lines 3-3 of Fig. 1- but showingsome-of the elements inelevation;

4'is across sectional view taken substantially along the lines 44- ofFig.3 and Fig. 5 is a cross'sectionalview taken substantially along thelines 5-5 of Fig. 4.

The novel control valve of the present invenare positioned in thepassageway, hereinafter described, connecting the inlet 20 and theoutlet 22. The inlet 26 is adapted to be connected to a fuel pump orother suitable source for supplying fuel under pressure, while theoutlet 22 may be connected directly to the inlet to an internalcombustion heater. tThe inlet 20 isconnected to passageway 24 formed inapproximately the center of the valve body Ill, passageway 24 leading toa cross passageway 28 at right angles thereto. Passageway 26 isconnected to an enlarged cylindrical threaded bore 28 into which theautomatic pressure'regulator l2 of well known construction is threaded.Leakage past the pressure regulator l2'is prevented by a sealing gasket30 which-is heldaga inst a shoulder 32' at the upper end of the bore 28by the upper end of the pressure regulator t2; The outlet of thepressure regulator l2 opens into an enlarged cylindrical chamber 34formed in a depending portion 3 6 of the valve body. The chamber 34 isclosed by a flexible diaphragm'38 which is held at its outer edgebetween a circumferential flange 49 formed on a domelike'housing 42 andthe depending portion 36.

'The flang'e 40 and diaphragm 38 are secured'to thefcasting Ill bysuitable machine screws 44, and the diaphragm 38 thus forms a fluid andpressure tight seal for the' chamber 34 against theatmosphere f g I Atits center, the diaphragm 38 is retained between a largecup-like washer46 and the head of a rivet 48.-. The washer 46 has a roundedperipheraledge lying against the diaphragm 38 to prevent cutting. the diaphragm.when itis flexed upwardly, as seen inFig. 3. The diaphragm 38 is urgedupwardly against the pressure in the chamber 3&- by a spring 50 which isheld between a pair of cups 52 and 54, the cup 52 being a part of thewasher and the rivet structure-and the cup 54 being fixedly mounted onthe end ofan r es 3 adjustment screw 56 which is threaded into the domeof the housing 42.

The head of the rivet 48 bears against the lower end of a valve stem 58of the automatic pressure regulator I2; when the pressure in the chamber34 drops below a predetermined desired value, the spring 50 flexes thecenter of the diaphragm and moves the valve stem 58 upwardly therebyfurther openin the valve in the automatic pressure regulator I2 toincrease the fuel fiow and the pressure in the chamber 34.

A passageway 68 lead away from the cham ber 34 toward the solenoidcontrolled valve I4, which controls the flow of liquid fuel throughvalve port 62. The valve port 62 and thepassageway 60 communicate with avalve chamber 64 in which reciprocates a valve body 66 formed as amovable iron core armature of the solenoid.

The solenoid comprises winding 88 having a conductor I and agroundterminal I2, the movable armature 66, and a fixed iron core I4. Thesolenoid winding is wound around an insulating sleeve I6. The sleeve 76has a friction-fit engagement witha second sleeve I8 formed of anon-magnetic metal such as brass which is tapered at 80 to insure propercentering relative to the iron core I4 and so that the sleeve I6 iseasily started during assembly. The solenoid winding 68 is covered witha wrapping 82 of an impregnated insulating material and is covered by asecond sheet of a similar material 84, which is wrapped around theconductor I0 to insulate it from contact with the metal parts of thecontrol valve. 7 The sleeve [8 is rolled back at 86 and is provided witha flange 88 which is positioned in a recess 80 in the casting I0 andwhich with a gasket 02 forms a pressure and fluid tight seal for thevalve chamber 64 against the atmosphere. The fiange 88 and the gasket 92are retained in the recess 90 by thebottom wall of a housing .94 made ofiron or some similar magnetic flux conducting material. The housing 94is secured to the casting valve body ID by suitable bolts 96 and has anopening 98 to accommodate the sleeve .78. At its opposite end, thesleeve 18 is rolled inwardly at I00 against the outer end of the fixediron core I4 so that the core fixe the end of the sleeve, as will appearpresently. As the inside of the sleeve I8 is open to the valve chamber64, it is insulated-against pressure and fluid leakage by a gasket I02secured in a circumferential groove I03 in the iron core I4. Thesolenoid winding 68 is positioned in the housing 94 and is .connectedatone end to a terminal washer I04 secured between the end of the sleeve18 and a housing cover I06 by means of a machine screw I08 threaded intothe iron core 14. The circuit through the solenoid winding may be tracedthrough the conductor I0, solenoid winding 68, terminal lead I2, washerI04, and to ground. The cover I06 for the housing is provided with anopening III] for the conductor 10 inwhibh is secured a synthetic rubbergrommet I12;

4 H8 is rolled into a groove I24 in the arma ture 66.

When'in closed position, the synthetic rubber pad I I6 seats against acircumferential valve face I26 surrounding the port 62 and seals theport 62 against communication with the chamber 64. When the solenoid isenergized by its controlling circuit, a magnetic field is setup whichbridges the air gap between the movable armature 66 and the iron core I4thereby moving the armature 66 to the right to open the port 62 toestablish communication between the chamber 64. passageway 6fl,andchamber 34 on the one hand and passageway I36 leading from .port 62 onthe other hand. The magnetic circuit is set up through the housing 94,housing cover I06, iron core "I4, and movable armature 66, and the fieldso 'set up closes the air gap existing between the core I4 and. thearmature 66 to open the on-ofi valve I4. Thus the magnetic field has asubstantially closed path through materials of high permeability. It isto be noted that the armature 66 slides freely in the sleeve I8, andthat this sleeve is ordinarily filled with liquid fuel since it is inconstant communication with the chamber 64, but leakage of the fuel fromthe sleeve I8 is prevented by the gasket I82.

Solenoid valve I6 has a construction identica with that of solenoidvalve I4 and, consequently, need not be described in detail. It includesa movable armature I28 which reciprocates in a chamber I30- The chamberI30 i connected to the port 62 through passageways I32, I34, and

I36, which are drilled or cored in the casting I0 (Fig. 3) andcommunicates with the outlet 22 through passageways I38 and I40 (Fig.5).

When the solenoid valve I6 is closed and the solenoid valve I4 is open,fuel is fed to the outlet 22 through the flow of restricting means I8which has its inlet connected to thepassageway I34 and which isconnected to the passageway I40 through a cross passageway I42. The fiowrestricting means I8 is formed generally by placing a plurality of verytiny orifices in series in a passageway which connects the passagewayI34 with the passageway I42. The orifices are formed in a thin sheetmetal plate I44 which is retained between a pair of gaskets I46 and I48.The gasket I46 is placed against a smooth, machined surface I 50 on thevalve body I0 and the upper surface of gasket I48 is engaged by theunder surface of a circular retaining plate I52. The assembly of theorificed plate I44, gaskets I46 and I48, and plate I52 is mounted insandwich form on the valve body I I) by machine screws I54. Thearrangementof the orifices in the plate I44 is most clearly shownin Fig.4. The'fuel flows through the orifices in the following order: I56, 158,I60, I62, I64. I66, m, and no. Orifice I56 is in communication withpassageway I34 through a circular opening H2 in the gasket l 46 (Fig.3). Orifice I56 is in communicationrwith orifice I58 through a slot I14formed in gasket I48. In turn, orifice 1 I58 communicates with orificeI68 through a similar opening I-I6 formed in gasket I46. A similarlyshaped opening-I18 is formed in gasket I48 to connect the orifice ;I60with orifice I 62 which, in turn, communicates with orifice I64 by meansof a slot 'I18-formed in gasket I46. Slot I80, formed in gasket I48,connects orifice I64 with orifice I66, which is placed in communicationwith orifice I68 through an opening'I82 in gasket I46, and orifice I68communicates with outlet orifice I I0 through an opening I84 formedinthe gasket I48. The slots which have been described as1 .b eing.formedin thegaskets I46 and I43 formthesepassageways connecting adjacentorifices in the plate. I44.- by being confined between the casting III.and :the orificed plate I44, and between plate I44 andthe retainingplate I 52, respectively. I This COnStruC? tion, is clearly shown inFigs. 3- and 5.. Whenv the shut-off valve I4'is open and the valve I 6is closed, thefuel; will be meteredthrough these minute orifices whichare arranged in series between; the gri andindividuallymounted onthecasting Iii-on an outwardly facing surface: 1 I In assemblingthecontrol valve,- the automatic pressureregulatorfl is screwed into thethreaded opening-28 afterthe gasket 30 has been placed against the.shoulder 3-2. placed over the vend of -the automatic pressure regulatorso that the rivet48 engages the valve stem 58. The coil springficisconfinedbetween the cups 52 and 54 asthe dome-like housing 42 ismounted on the casting Iilby the machine screws- 44. If, for example, itis desired that the pressure of the fuel in the chamber =34 be 1 p. s.i. gauge, the action of the diaphragm'ds adjusted to drop the pressureat the inlet 28 which'maybe 3-or. d pusi ifgauge, to 1 p. s. i. in thechamber 34. In order accurately to obtain this regulation, thecompression on the spring 50is-carefully adjusted by'means ofithe screw56. When this adjustment has been made, the screw maybe secured inposition by placing a ring of solder I86 around the screw 56 where itcontacts the dome-like housing 42.

The flow restricting means I8 may then be mountedon the casting I0.Gasket I46 isplaced against the machined surface I50 on the casting I0;Orificed plate I44 and-gasket I48 are, in turn, laid-on'the top ofgasketllltf, and then the retaining'plate' I52 is putin position, thewhole being secured to the casting I0by means of the machine screws I54.The-gaskets are compressed slightly so as to provide a' pressure andfluid tight seal in the passageways'formed by the retaining plate I52,gaskets I46 and I48, plate I44, and casting I0. Care must be taken toinsure the proper sequential relationship betweenv the orifices formedin the plate I44 and the slots formed'in each of the gaskets I46 andI48. In order that this might be facilitated, the mounting holes in theplate I44, gaskets I46 and I48, plate I52 and casting ID are offsetrelative to a symmetrical or equi-angular spacing so that they mayassume only one position relative to each other with the mounting holescoinciding.

The solenoid control valves I4 and I6 may then be readily assembled onthe casting I0. The sub-assembly of the sleeve 18, iron core I4, andarmature 66 is assembled before mounting'the casting I0. Thissub-assembly is mounted with The diaphragm 38 is accents respectiveholes to secure the sleeve and movable elements of the valve to thecasting I10. The solenoid winding 68, which has previously been wound onthe sleeve I6, may then he slid onto. the sleeve 18 with which thesleeveIG is in friction engagement. The solenoid winding carries thewasher I04 which is held securely against the housing cover I06 by thescrew I08. .Theother solenoid controlled valve I6 .is assembled in asimilar manner.

The control valve forming the subject matter of this invention isparticularly well adapted for supplying liquid fuel to an internalcombustion heater at the rate required to maintain'the'output of theheater suflicient to maintain the temperature of the space being heatedat a desired and controllable level. For example, in starting theheater, it might be required that it deliver a maximum output of 20,000E. t. u. per hour. The control valve, which has been described, and withthe pressure examples which have been given in the description, whichare at between 3 and 4 p. s. i. gauge pressure at the inlet 20 'and .l'p. s. i. gauge pressure in the chamber 34, will be in fully openposition. In thisv positiomthe solenoid controlled valves I4 and I6 areboth open, that is, the solenoids are energized-so as to move the valvearmatures 66 and I28 tothe right and to the left, respectively (Fig. 3)When the space to be heated has warmed to a predetermined temperature,and it is desired merely-to maintain that temperature, the solenoidcon-a trolled valve IE will be tie-energized and the spring biasedarmature valve body I28 willmove to the right, shutting off the flow offuel between the valve chamber I30 and thepassageway I38;

the flange 88 in the recess 90 in such position as to hold the gasket 92against its seat and to position the rolled edge 86 slightly within thevalve chamber 64. The housing 94 is then slipped over the sleeve I8 andagainst the flange 88 to hold the sleeve I3 and associated parts inplace, and the machine screws 96 are threadedinto their This shuts offthe flow of fuel from the chamber 64 through the chamber I30 to theoutlet 22 'via the passageways I34, I32, and I38. I However, the chamber64 is in communication with the passageway I34 through the open port 62,and the passageway I34-is in communication with the outlet 22 andpassageway I42 leading thereto through the flow restricting means Itwhich comprises the tortuous passageway formed by the'casting It, gasketI40, plate I44, gasket I48, and retaining plate I52. This tortuouspassageway is provided with the plurality of interconnected orificesI56, I58, I85, I62, I54, I58, and 510, which reduce the flow rate sothat the heater output will be approximately 5,000 B. t. unper hour. Ifthe temperature of the space to be heated then drops below asatisfactory level, the valve I6 is reopened to establish high heatoperation.

If the-temperature in the space to be still rises above the desiredmaximum, or if the heater tends to overheat, even though valve It isclosed, it may be desirable to interrupt heater operation, in which casethe solenoid, valve I4 closes through the deenergization of its circuit.

When the fuel feeding system to the heater is in operation, the chamber34, the valve chambers 64 and I30, and all of the passageways in thevalve body III will be completely filled with fuel. Thus there will beno air pockets present and the flow of fuel from the outlet 22 will beinstantaneous upon opening the valve, and at a rate determined by thepositions of the solenoid valves I4 and I6.

The examples for thermal output of the heating system and the fuelpressures which have been given in the foregoing description of thisinvention are merely illustrative, and it is to be understood that theymay vary according to the heated 7 particular installation. Should therequired pressure drop between the chamber 34 and the outlet 22throughthe restricting means 18 be greater than that which can be-obtained withthe number of orificesillustrated herein, more orifices may be used inthe series. Conversely, fewer. or larger orifices may be used when lessrestricting effect is desired.

While. there has been described but a single embodiment of theinvention, it is appreciated that changes and modifications maybe madetherein without departing from the sphere and scope of the-invention,therefore, what is desired to be claimed as new and secured by UnitedStates Letters Patent is:

1. A liquid flow restrictor comprising a thin plate having a pluralityof tiny orifices formed therethrough from face to face, said orificesbeing of such size andnumber that the pressure drop through a seriesconnection of said orifices produces the desired restricting effect, andpassage forming means having substantially no restricting, effectdisposed on both sides of said plate for connecting said orifices inseries so as tocause liquid to fiow alternately from one side ofsaidplate to the other by way of said orifices.

2. A liquid flow restrictor comprising a body portion having a fiatface,said body portion being formed to provide liquid inlet and outletconnections and passages leading from said connections respectively toliquid inlet and outlet ports formed in said fiat face, a cover having aflat surface adapted to cover said ports, means forsecuring said coverto said body portion, a

- thin flat plate disposed between said body portion and said cover,said plate having a plurality of small orifices'formed therethrough fromface to face, a body gasket disposed between said body and said plate, acover gasket, disposed between said cover and said plate, said bodygasket having aplurality of apertures formed therein which formindividual spaces when said body gasket is confined between said bodyand said plate, one of said spacesintersecting said inlet port andanother of said spaces intersecting said outlet port, said cover gaskethaving a plurality of apertures formed therein which form individualspaces when said cover gasket is confined between said cover and saidplate with the apertures in said cover gasket disposed so as tointersect and interconnect the apertures in said body gasket, theorifices in said plate being located with one at each of saidintersections so that the liquid is required to flow back and forthbetween the two faces of said plate by way of said orifices as theliquid passes from said inlet port to said outlet port, and saidorifices being "8 so small as comparedwith said spaces thatsubstantially all of the restricting effect on said liquid is due to theseries arrangement of said small orifices.

3. A liquid flow restrictor comprising a pair of members having fiatfaces, a thin plate clamped between said faces, said plate having aplurality of small orifices therethrough from face to face, a pair ofgaskets disposed with one between said plate and one of said members andthe other between said plate and the other of said members, one of saidgaskets having a plurality of apertures therein with each of saidapertures overlapping separate pairs of said orifices so that saidorifices are connected into individual sets of two each'by the passagesformed by said apertures when said one gasket is confined between saidplate and its member, the other of said gaskets having a plurality ofapertures therein with each of the last said apertures overlapping otherseparate pairs of said orifices so thatsaid orifices are connected intoindividual sets of two each by the passages formed by the apertures insaid other gasket when said other gasket is confined between said plateand its member such that said orifices are connected in series by thepassagesformed on alternate sides of said plate, means for establishingliquid inlet and outlet connections at opposite ends of said series, andsaid orifices being so small as compared with said passages thatsubstantially all of the restricting effect on said liquid is due tosaid orifices in series.

GEORGE W. ALLEN. VERNON N. TRAMONTINI.

REFERENCES CITED UNITED STATES PATENTS Number Name Date 353,227 KuylNov. 23, 1886 874,517 Lowry Dec. 24, 1907 1,057,943 Dalen Apr. 1, 19131,652,171 Hufi' Dec. 13, 1927 1,964,300 Perry et a1 June, 26, 19341,983,227 Hall et a1. Dec. 4, 1934 2,118,290 Black May 24, 19382,118,295 Crawford May 24, 1938 2,210,448 Dodge Aug. 6, 1940 2,236,084Brown Mar. 25, 1941 2,310,745 Parks 1 Feb. 9, 1943 2,343,806 ScofieldMar. 7, 1944 FOREIGN PATENTS Number Country Date France Apr. 3, 1912

